This invention relates to barrier control means and in particular, to a security barrier for use in controlling vehicular access to parking areas and passageways such as highways and byways by use of a retractable barrier denominated "Scopelock."
In view of the proliferation of vehicular traffic in cities and urban areas, there is an increasing need for controlling access of such vehicles in parking areas and roadways. It is particular important in maintaining security and availability of parking around emergency areas such as ambulance parking areas as well as paid parking and private parking areas.
In the past, various means of controlling parking space access and roadway travel have been proposed. In one such example, U.S. Pat. No. 3,849,936, employs a barrier plate which is pivotal along one side from a horizontal to a near vertical position. This particular invention requires a barrier that is substantially the length or width of the entire vehicle, consequently adding cost and expense. U.S. Pat. No. 4,715,742 to Dixon, describes an anti-terrorist barricade capable of stopping movement of vehicles unauthorized to enter a trafficway. The mechanism includes a spring lift means with a trigger mechanism which upon triggering, releases the spring and a bollard (or barrier) is erected. Such a system would be subject, of course, to environmental exposure which could cause operating problems. U.S. Pat. No. 4,576,508 to Dickenson, describes a bollard type trafficway barrier for arresting vehicles which includes a hydraulic lift that requires a sufficient source of hydraulic power and is subject to underground environmental exposure and thus is somewhat undesirable. This system is somewhat complicated and is practically not feasible for widespread use in routine parking or traffic control applications.
Other systems utilize gates such as that described in U.S. Pat. No. 3,368,305 to Piekarski, which is currently a typical installation in parking areas in such regions as airports and downtown parking lots, hospital areas and other private parking areas. Such devices suffer from being easily damaged by a vehicle running into the gate or the mechanism failing to operate for other reasons and, of course, such things are subject to vandalism since the mechanism is entirely above ground. There are little, if any, provisions in the prior art for mechanically raising or lowering the barrier if, for whatever reason, there is a power failure or other mechanical failure in the power source whether electric or hydraulic.